Project Summary/Abstract The Automated Biological Calorimetry facility at Pennsylvania State University requires a low-volume Isothermal Titration Calorimeter (ITC) for use in a research environment. We have identified the TA Instruments Auto Affinity ITC as the sole commercial product which meets our requirements. The active volume of the cell made of gold, is the lowest available in the market at 190 ?L. Having low volume is paramount for the success and throughput of all the life science related projects described in this proposal, as purifying biological samples such as proteins, peptides, carbohydrate, lipids and nucleic acids is labor and cost intensive. The equipment we seek has solid- state thermoelectric devices for both active heating and cooling to maintain accurate, precise temperature control. The injection system is independent of and does not spin with the stirring mechanism. The injection system incorporates a glass injection syringe into the body of the automated injection arm of the instrument. The injection cannula shoots the sample at the top of the stirring paddle of the stirring system for more efficient mixing at lower stir rates. Higher stir rates can introduce unwanted noise into the measurement, and can potentially damage delicate protein and DNA structure. Lower noise in ITC runs leads to improved sensitivity. This would be crucial for weak binders we typically come across in our core and for binding studies with some of our samples with lower solubility such as carbohydrates and peptides. Cleaning of the stirring and injection systems is user programmable and fully automated in the Affinity-ITC instrument. It also includes an automation accessory, a reliable autosampler for high throughput sample handling. The controlling and analyzing software is user friendly and loaded with features for thermodynamic analysis for a variety of binding models. The autosampler does not require positional calibration, and includes a self-centering mechanism to ensure precise and repeatable syringe placement in the measurement cell. The instrument currently running at the core facility is the AutoITC200 by Malvern company. This was the first generation instrument of its kind when procured in 2009 and is prone to frequent maintenance issues due to its age and constant use. It has many moving robotic parts that crash with software errors, fine tubing that gets easily blocked and is in general need of replacement. The ideal instrument for our requirement is the state-of-the-art, high-throughput low volume TA Affinity-ITC instrument that has shorter tubing, fewer moving robotic parts and is simpler in design. A highly sensitive ITC equipment is crucial to the success of the eleven NIH projects pursued on our campus that the facility can address.